    <div id="signin" class="modal fade in" style="display: block">
        <div class="modal-dialog">
            <div class="modal-content">
                <div class="modal-header text-center">
                    <button type="button" class="close" data-dismiss="modal"><span  aria-hidden="true">&times;</span><span class="sr-only">Close</span></button>
                    <h2 class="modal-title">Sign in</h2>
                </div>
                <div class="modal-body">
                    <h3>Great to have you back!</h3>
                    <form role="form">
                        <div class="form-group">
                            <label for="accountInput">Username</label>
                            <input type="text" class="form-control" maxlength="18" id="accountInput" placeholder="请输入账号">
                        </div>
                        <div class="form-group">
                            <label for="passwordInput">Password</label>
                            <input type="password" class="form-control" maxlength="18" id="passwordInput" placeholder="请输入密码">
                        </div>
                        <button type="button" class="btn btn-success btn-lg">Sign in to your account</button>
                        <p>New here? <a href="#">Create an account</a></p>
                    </form>
                </div>
            </div><!-- /.modal-content -->
        </div><!-- /.modal-dialog -->
    </div><!-- /.modal -->
